In nuclear medicine (NM) imaging, such as single photon emission computed tomography (SPECT) or positron emission tomography (PET) imaging, radiopharmaceuticals are administered internally to a patient. Detectors (e.g., gamma cameras), typically installed on a gantry, capture the radiation emitted by the radiopharmaceuticals and this information is used, by a computer, to form images.
However, during NM imaging motion from the patient affects the resultant image. During a scan of the patient multiple 2D slices are accumulated to form a 3D image of the patient. Objects of the patient need to be monitored during the scan to adjust for motion of the patient. For example, the objects need to detect the contour of the patient before the detectors approach the patient, and should be adjusted in case the patient moves during the scan. Conventional methods use forms of filtering and/or segmentation to identify a position of the objects extending a length of the scan. Alternatively, conventional systems use Computed Tomography (CT) during the scan, which exposes the patient to additional radiation.